富勒烯衍生物(C36OH)+异构体间的相互转化机理──羟基(OH)的分子内迁移

用从头算HF/STO-3G方法对(C36OH)+的3种异构体之间的重排机理进行了理论研究.计算结果表明,异构体2的热力学稳定性最强;从动力学角度考虑,由异构体1和3转化为2比反方向转化容易得多.结合电荷在碳笼表面的分布,预计动力学上最终在C7和C26位置上发生羟基加成的几率最大,该结论与热力学上预计的跨赤道六元环内羟基1,4-加成所得到的C36(OH)2异构体最稳定的结果一致.

Ab initio Investigation of the Rearrangement Between the Isomers of C36 Fullerene Derivative(C36OH)+——Intramolecular OH-shift

The mechanism of the rearrangement between the isomers of (C 36 OH) +, one of C 36 fullerene derivatives, has been investigated by ab initio calculation at HF/STO 3G level. The result shows that isomer 2 is thermodynamically the most stable, and kinetically it is much easier to convert isomers 1 and 3 into 2 than to convert 2 into 1 and 3 judging from the calculated energy barriers. On the other hand, the distribution of the charges on the cage of the (C 36 OH) + isomers implies relatively more probability for the addition of OH group to the 1,4 sites in the six membered ring locating at the equatorial belt of the C 36 cage than to the other sites, which agrees with the themodynamic stability of the C 36 (OH) 2 isomers.